This invention relates to a vehicle hitch, and more particularly to an automatic trailer hitch.
Trailer hitches, including automatic trailer hitches, are well known in the art. Examples of some of these hitches are disclosed in the following U.S. Pat. Nos.:
______________________________________ 2,579,232 Hansen Dec. 18, 1951 3,046,037 Cain July 24, 1962 3,744,819 Cook et al July 10, 1973 3,865,407 Klassen Feb. 11, 1975 3,912,302 Patterson Oct. 14, 1975 4,389,058 Cadwell June 21, 1983 4,484,760 Rach Nov. 27, 1984 ______________________________________
All of the above patents disclose various types of remote-controlled trailer hitches.
Hansen, Cook et al, Klassen, and Patterson disclose coupling hitch pins connected to a remote-controlled cable for lifting the pin in order to disengage the draft vehicle from the trailer vehicle.
Cain, Cook et al, and Patterson disclose hitch coupling pins which are spring-biased downwardly toward engagement between the draw bar and the trailer tongue, when the corresponding pin holes are aligned.
Cadwell and Rach disclose remote-controlled hitch assemblies which are associated with a three-point hitch of a tractor, but the coupling hitch pins are positively driven up and down by power means.
The Patterson patent discloses a spring-biased coupling pin urged downwardly toward locking position, and a cable connected to the coupling pin for lifting the pin to an unlatched position by remote control. Patterson further discloses a release mechanism adapted to be engaged by the front end of the trailer tongue, including a release pin 66 biased rearward by a spring. However, when the impact head 74 of the release pin 66 is urged forward by engagement of the front end of the tongue, a latch is released to permit the descent of the spring-biased coupling pin into engagement with the aligned holes in the draft bar and the trailer tongue. Patterson's release mechanism involves several operative link elements, including a pivotal latching mechanism 60 having a catch 78 adapted to engage the shoulder 80 on a pivotal bell-crank operatively connected to the pull cable 82 and through another bellcrank arm to a disk stop 52 on the coupling pin 40.